Mailing systems, such as, for example, a mailing machine, often include different modules that automate the processes of producing mail pieces. The typical mailing machine includes a variety of different modules or sub-systems each of which performs a different task on the mail piece. The mail piece is conveyed downstream utilizing a transport mechanism, such as rollers or a belt, to each of the modules. Such modules could include, for example, a singulating module, i.e., separating a stack of mail pieces such that the mail pieces are conveyed one at a time along the transport path, a stripping/moistening module, i.e., stripping open the flap of an envelope, wetting and sealing the glued flap of an envelope, a weighing module, and a metering/printing module, i.e., applying evidence of postage to the mail piece. The exact configuration of the mailing machine is, of course, particular to the needs of the user. Other types of mailing systems, such as, for example, inserters, feed material from one or more trays to be inserted into awaiting envelopes whose flaps have been opened and then sealed when the contents have been inserted.
Typically, a stripping device includes a structure for deflecting a flap of a moving envelope away from the envelope's body to enable the moistening and sealing process to occur. The deflecting structure typically includes a stripper blade that becomes inserted between the flap of the envelope and the body of the envelope as the envelope traverses the transport deck of the mailing machine. Once the flap has been stripped, a moistening device moistens the glue line on the envelope flap in preparation for sealing the envelope. Typically, a moistening fluid is deposited onto the envelope flap to activate the glue. The flap is then closed and sealed, such as, for example, by passing the closed envelope through a nip of a sealer roller to compress the envelope and flap together, and the envelope passed to the next module for continued processing.
In typical moistening applications, it is desirable to maintain a catch basin beneath the moistening device to collect moistening fluid that is discharged by the moistening device but not carried away by the envelope. Preferably, this moistening fluid is recycled and stays within the moistening device for subsequent usage. Unfortunately, this fluid becomes contaminated with different materials derived from the paper and adhesive. Contaminants include, for example, envelope adhesive and paper dust, comprising paper fibers and filler used to make paper envelopes, which are released by the friction associated with the envelope contacting different parts of the mailing system, such as the stripper/moistening module. Such contaminants negatively impact the operation of the moistening device such as, for example, clogging of components that supply the moistening fluid to the different parts of the moistening device. These situations can result in insufficient moistening fluid being applied to the envelope flaps, which results in inconsistent sealing of the envelopes.